Table 1 Baseline characteristics of ICU patients in the training and hold-out test sets.
Training data set (n = 23,517) | Hold-out test set (n = 5900) | |
|---|---|---|
Patient demographics | ||
Age, years | 67 [53–76] | 66 [53–75] |
Sex | ||
Female | 10,047 (42.7%) | 2541 (43.1%) |
Male | 13,470 (57.3%) | 3359 (56.9%) |
Co-morbidities | ||
Chronic heart failure | 3768 (16.0%) | 924 (15.7%) |
Cirrhosis | 894 (3.8%) | 235 (4.0%) |
AIDS | 32 (0.1%) | 8 (0.1%) |
Metastatic cancer | 1220 (5.2%) | 279 (4.7%) |
Haematological cancer | 870 (3.7%) | 263 (4.5%) |
Cancer therapy | 938 (4.0%) | 236 (4.0%) |
Admission category | ||
Medical | 13,065 (55.6%) | 3331 (56.5%) |
Scheduled surgery | 3134 (13.3%) | 746 (12.6%) |
Unscheduled surgery | 7318 (31.1%) | 1823 (30.9%) |
Type of surgery | ||
Transplantation: Liver, kidney, pancreas | 100 (0.4%) | 39 (0.7%) |
Transplantation: Kidney and pancreas, other | 1 (0.0%) | 0 (0.0%) |
Cardiac surgery | 324 (1.4%) | 101 (1.7%) |
Trauma | 801 (3.4%) | 205 (3.5%) |
Neurosurgery | 559 (2.4%) | 136 (2.3%) |
In-hospital location before ICU admission | ||
Emergency room | 6882 (29.3%) | 1640 (27.8%) |
Other ICU | 1953 (8.3%) | 528 (8.9%) |
Hospital ward, recovery unit, or operating room | 14,682 (62.4%) | 3732 (63.3%) |
Length of hospital stay before ICU, days | 1.0 [0.0–3.0] | 1.0 [0.0–3.0] |
Length of ICU stay, days | 1.5 [0.8–4.1] | 1.6 [0.8–4.0] |
Number of admissions | ||
1 admission | 19,272 (81.9%) | 4830 (81.9%) |
2 admissions | 3081 (13.1%) | 742 (12.6%) |
3 admissions | 755 (3.2%) | 216 (3.7%) |
≥ 4 admissions | 409 (1.7%) | 112 (1.9%) |
Mortality | ||
ICU mortality | 3154 (13.4%) | 806 (13.7%) |
In-hospital mortality | 5715 (24.3%) | 1458 (24.7%) |
90-day mortality | 7198 (30.6%) | 1809 (30.7%) |
